1. Field of the Invention
This invention relates to electrostatic copiers and more particularly to support assemblies for components thereof.
1. Prior Art
This invention is directed to that class of device generally known as a nonmechanical printer or copier in which operating units for generating charge patterns on an intermediate carrier, for developing the charge patterns with toner, and for transferring the toner images onto a recording carrier are positioned alongside the intermediate carrier. Such devices are herein collectively described as electrostatic copiers however it is to be understood that that term is used in an inclusive capacity. In such devices both the operating units and the intermediate carrier must be readily accessible without damange to either the unit or the carrier.
The production of images on a recording carrier such as, for example, a sheet of paper by electrostatic techniques in copiers or nonmechanical printers is well known. See for example U.S. Pat. No. 3,099,856. In such devices charge images or latent images of the symbols to be printed on the recording carrier are generated either electrographically or electrophotographically on an intermediate carrier which may, for example, be a drum with a dielectric or photoelectric coated surface. The latent images are developed at a developing station positioned along the circumference of the drum. Development is done with the aid of a toner to produce toner images on the intermediate carrier which images are thereafter printed onto the recording carrier at a transfer station positioned further along the circumference of the drum. At the transfer station the toner images are transferred from the drum surface to the recording carrier. The transferred images can later be fused onto the recording carrier at a fixing station. Further along the drum circumference from the transfer station may be positioned a drum cleaning unit for cleaning the drum surface of any toner residue. Also positioned along the drum circumference are means for applying a charge to the drum surface.
Thus a plurality of operating units are arranged adjacent the intermediate carrier. Such units either produce the toner image, i.e. the developing station and the transfer station or may exist for producing the latent image such as electric combs or light sources or for charging the surface such as a corotron.
Each of these units, for example the developing station unit, must be positioned very precisely in relation to the intermediate carrier. However for purposes of servicing the unit, either for eliminating faults or for replacement or cleaning of parts, both the intermediate carrier and the components of the unit must be easily and readily accessible. It is therefore desirable to separate the units and intermediate carrier quickly, precisely and without problem and to reposition them in the desired operating position quickly. However since both the components of the operating units and the surface of the intermediate carrier are sensitive, the means by which the units are to be separated must be such as to insure that they will not contact each other during separation.